Singer Sewing Machine 621B Manual

The Singer 621B is a classic mechanical sewing machine designed for home use, featuring straight stitch capability, built-in stitch length adjustment, reverse stitching function, drop-in bobbin system, built-in thread cutter, and various presser feet for different sewing applications. Below are key sections for safety, features, setup, operation, maintenance, and troubleshooting.

Features at a Glance

Key components: Mechanical sewing head, built-in stitch length control, reverse stitch lever, bobbin winder, presser foot lifter, feed dog system.

Installation & Setup

Unpack and inspect contents. Place on stable sewing table.

1. Remove protective packaging and position machine securely.
2. Connect foot pedal to machine and plug into power outlet.
3. Install needle: Loosen needle clamp screw, insert needle with flat side to back.
4. Wind bobbin: Place empty bobbin on winder, thread through tension disc.
5. Install bobbin: Drop bobbin into case with thread pulling counterclockwise.

WARNING! Keep fingers away from needle area during operation. Unplug when not in use.

First-Time Operation

Power on machine; test basic functions.

1. Upper threading: Follow numbered guides from spool to needle.
2. Pull up bobbin thread: Hold upper thread, turn handwheel toward you.
3. Test stitch: Place fabric under presser foot, lower foot, and begin sewing.
4. Adjust stitch length: Turn dial for shorter or longer stitches.
5. Practice reverse stitching: Engage reverse lever at beginning and end of seams.

CAUTION! Always turn handwheel toward you only. Never force the machine.

Specifications

• Machine Type: Mechanical straight stitch
• Stitch Length: 0-4mm adjustable
• Bobbin: Class 15 transparent bobbin
• Needle System: 15x1 household needles
• Presser Feet: Standard snap-on system
• Maximum Speed: 800 stitches per minute
• Power Requirements: 110-120V, 60Hz
• Weight: 12.5 lbs (5.7 kg)
• Dimensions: 15" x 7" x 12"

Controls and Settings

Main controls located on machine body: Stitch length dial, reverse stitch lever, handwheel, bobbin winder, tension dial.

Stitch Length Dial: 0-4mm adjustment (0 for bobbin winding). Reverse Lever: Hold down for back-tacking. Tension Dial: Higher numbers for tighter tension. Presser Foot Lever: Raises and lowers presser foot. Bobbin Winder: Push to right for winding, left for sewing.

Threading the Machine

Follow numbered threading path from spool pin to needle.

1. Place thread spool on spool pin.
2. Pull thread through first thread guide on top.
3. Pass thread through tension discs from right to left.
4. Thread through take-up lever from right to left.
5. Follow remaining guides down to needle.
6. Thread needle from front to back.

Tip: Always raise presser foot when threading to release tension discs.

Basic Sewing Operations

Straight stitching for seams, hems, and basic construction.

1. Position fabric under presser foot with raw edge aligned.
2. Lower presser foot and needle into fabric.
3. Begin sewing with steady foot pedal pressure.
4. Guide fabric gently without pulling or pushing.
5. Use reverse stitch at beginning and end of seams.
6. Raise presser foot and pull fabric to back to remove.
7. Use built-in thread cutter to trim threads.

WARNING! Never sew over pins. Remove pins before they reach needle.

Maintenance & Cleaning

Regular maintenance ensures optimal performance.

1. Clean lint from bobbin area after each project.
2. Oil machine according to lubrication points diagram.
3. Change needles regularly (every 8-10 hours of sewing).
4. Wipe exterior with soft, dry cloth.
5. Store covered when not in use.

CAUTION! Unplug machine before cleaning or maintenance. Use only sewing machine oil.

Accessories Included

• Standard presser foot
• Zipper foot
• Buttonhole foot
• Class 15 bobbins (3)
• Needles (assorted sizes)
• Seam ripper/lint brush
• Screwdriver
• Power cord and foot pedal

Warranty Information

Singer Limited Warranty: 25 years on mechanical parts. Proof of purchase required. Warranty covers defects in materials and workmanship. Does not cover damage from misuse, improper maintenance, or commercial use. For warranty service, contact authorized Singer service center.

Troubleshooting

Service: Contact authorized Singer service center. Visit www.singer.com or call 1-800-4-SINGER.